外电场对HMX/DMI共晶感度影响的理论研究

To clarify the influence of external electric field on the sensitivity of energetic HMX/DMI cocrystal material, various external electric fields (±0.005, ±0.010, 0.00a.u.) were applied on the stable configuration and corresponding electron density shift, nitro group charge, molecular surface electrostatic potential and trigger bond change were analyzed computationally through DFT-B3LYP-D3, M06-2X-D3 and ωB97XD methods with the 6-311+G(d, p) basis sets. The results show that the sensitivity of HMX/DMI was high/low when the applied external electric field was positive/negative. When the negative external electric field was stronger, the density of the bond electron cloud was higher as well as the bond strength of the trigger bonds. The negative charge of the nitro group increases from 0.126e to 0.325e when the negative external electric field was applied, which results in the lower sensitivity of HMX/DMI. The electrostatic surface potential (ESP) illustrated that the higher ESP is, the lower sensitivity of cocrystals is when using the negative external electric field. Trigger bond change analysis shows that the bond length of the trigger bond reduced from 0.1386nm to 0.1367nm, the dissociation energy of the trigger bond increased from 180.252kJ/mol to 180.782kJ/mol, and the sensitivity of the cocrystal compound decreased, while increasing the negative external electric field strength.